package ethchain
import (
"bytes"
"encoding/hex"
"fmt"
"github.com/ethereum/eth-go/ethutil"
"github.com/ethereum/eth-go/ethwire"
"github.com/obscuren/secp256k1-go"
"log"
"math"
"math/big"
"strconv"
"sync"
"time"
)
type BlockProcessor interface {
ProcessBlock(block *Block)
}
type BlockManager struct {
// Mutex for locking the block processor. Blocks can only be handled one at a time
mutex sync.Mutex
// The block chain :)
bc *BlockChain
// Stack for processing contracts
stack *Stack
// non-persistent key/value memory storage
mem map[string]*big.Int
TransactionPool *TxPool
Pow PoW
Speaker PublicSpeaker
SecondaryBlockProcessor BlockProcessor
}
func AddTestNetFunds(block *Block) {
for _, addr := range []string{
"8a40bfaa73256b60764c1bf40675a99083efb075", // Gavin
"93658b04240e4bd4046fd2d6d417d20f146f4b43", // Jeffrey
"1e12515ce3e0f817a4ddef9ca55788a1d66bd2df", // Vit
"1a26338f0d905e295fccb71fa9ea849ffa12aaf4", // Alex
} {
//log.Println("2^200 Wei to", addr)
codedAddr, _ := hex.DecodeString(addr)
addr := block.GetAddr(codedAddr)
addr.Amount = ethutil.BigPow(2, 200)
block.UpdateAddr(codedAddr, addr)
}
}
func NewBlockManager(speaker PublicSpeaker) *BlockManager {
bm := &BlockManager{
//server: s,
bc: NewBlockChain(),
stack: NewStack(),
mem: make(map[string]*big.Int),
Pow: &EasyPow{},
Speaker: speaker,
}
if bm.bc.CurrentBlock == nil {
AddTestNetFunds(bm.bc.genesisBlock)
bm.bc.genesisBlock.State().Sync()
// Prepare the genesis block
bm.bc.Add(bm.bc.genesisBlock)
//log.Printf("root %x\n", bm.bc.genesisBlock.State().Root)
//bm.bc.genesisBlock.PrintHash()
}
log.Printf("Last block: %x\n", bm.bc.CurrentBlock.Hash())
return bm
}
func (bm *BlockManager) BlockChain() *BlockChain {
return bm.bc
}
func (bm *BlockManager) ApplyTransactions(block *Block, txs []*Transaction) {
// Process each transaction/contract
for _, tx := range txs {
// If there's no recipient, it's a contract
if tx.IsContract() {
block.MakeContract(tx)
bm.ProcessContract(tx, block)
} else {
bm.TransactionPool.ProcessTransaction(tx, block)
}
}
}
// Block processing and validating with a given (temporarily) state
func (bm *BlockManager) ProcessBlock(block *Block) error {
// Processing a blocks may never happen simultaneously
bm.mutex.Lock()
defer bm.mutex.Unlock()
// Defer the Undo on the Trie. If the block processing happened
// we don't want to undo but since undo only happens on dirty
// nodes this won't happen because Commit would have been called
// before that.
defer bm.bc.CurrentBlock.State().Undo()
hash := block.Hash()
if bm.bc.HasBlock(hash) {
return nil
}
// Check if we have the parent hash, if it isn't known we discard it
// Reasons might be catching up or simply an invalid block
if !bm.bc.HasBlock(block.PrevHash) && bm.bc.CurrentBlock != nil {
return ParentError(block.PrevHash)
}
// Process the transactions on to current block
bm.ApplyTransactions(bm.bc.CurrentBlock, block.Transactions())
// Block validation
if err := bm.ValidateBlock(block); err != nil {
return err
}
// I'm not sure, but I don't know if there should be thrown
// any errors at this time.
if err := bm.AccumelateRewards(bm.bc.CurrentBlock, block); err != nil {
return err
}
if !block.State().Cmp(bm.bc.CurrentBlock.State()) {
return fmt.Errorf("Invalid merkle root. Expected %x, got %x", block.State().Root, bm.bc.CurrentBlock.State().Root)
}
// Calculate the new total difficulty and sync back to the db
if bm.CalculateTD(block) {
// Sync the current block's state to the database and cancelling out the deferred Undo
bm.bc.CurrentBlock.State().Sync()
// Add the block to the chain
bm.bc.Add(block)
/*
ethutil.Config.Db.Put(block.Hash(), block.RlpEncode())
bm.bc.CurrentBlock = block
bm.LastBlockHash = block.Hash()
bm.writeBlockInfo(block)
*/
/*
txs := bm.TransactionPool.Flush()
var coded = []interface{}{}
for _, tx := range txs {
err := bm.TransactionPool.ValidateTransaction(tx)
if err == nil {
coded = append(coded, tx.RlpEncode())
}
}
*/
// Broadcast the valid block back to the wire
bm.Speaker.Broadcast(ethwire.MsgBlockTy, []interface{}{block.Value().Val})
// If there's a block processor present, pass in the block for further
// processing
if bm.SecondaryBlockProcessor != nil {
bm.SecondaryBlockProcessor.ProcessBlock(block)
}
log.Printf("[BMGR] Added block #%d (%x)\n", block.BlockInfo().Number, block.Hash())
} else {
fmt.Println("total diff failed")
}
return nil
}
func (bm *BlockManager) CalculateTD(block *Block) bool {
uncleDiff := new(big.Int)
for _, uncle := range block.Uncles {
uncleDiff = uncleDiff.Add(uncleDiff, uncle.Difficulty)
}
// TD(genesis_block) = 0 and TD(B) = TD(B.parent) + sum(u.difficulty for u in B.uncles) + B.difficulty
td := new(big.Int)
td = td.Add(bm.bc.TD, uncleDiff)
td = td.Add(td, block.Difficulty)
// The new TD will only be accepted if the new difficulty is
// is greater than the previous.
if td.Cmp(bm.bc.TD) > 0 {
// Set the new total difficulty back to the block chain
bm.bc.SetTotalDifficulty(td)
/*
if ethutil.Config.Debug {
log.Println("[BMGR] TD(block) =", td)
}
*/
return true
}
return false
}
// Validates the current block. Returns an error if the block was invalid,
// an uncle or anything that isn't on the current block chain.
// Validation validates easy over difficult (dagger takes longer time = difficult)
func (bm *BlockManager) ValidateBlock(block *Block) error {
// TODO
// 2. Check if the difficulty is correct
// Check each uncle's previous hash. In order for it to be valid
// is if it has the same block hash as the current
previousBlock := bm.bc.GetBlock(block.PrevHash)
for _, uncle := range block.Uncles {
if bytes.Compare(uncle.PrevHash, previousBlock.PrevHash) != 0 {
return ValidationError("Mismatch uncle's previous hash. Expected %x, got %x", previousBlock.PrevHash, uncle.PrevHash)
}
}
diff := block.Time - bm.bc.CurrentBlock.Time
if diff < 0 {
return ValidationError("Block timestamp less then prev block %v", diff)
}
// New blocks must be within the 15 minute range of the last block.
if diff > int64(15*time.Minute) {
return ValidationError("Block is too far in the future of last block (> 15 minutes)")
}
// Verify the nonce of the block. Return an error if it's not valid
if !bm.Pow.Verify(block.HashNoNonce(), block.Difficulty, block.Nonce) {
return ValidationError("Block's nonce is invalid (= %v)", block.Nonce)
}
return nil
}
func CalculateBlockReward(block *Block, uncleLength int) *big.Int {
base := new(big.Int)
for i := 0; i < uncleLength; i++ {
base.Add(base, UncleInclusionReward)
}
return base.Add(base, BlockReward)
}
func CalculateUncleReward(block *Block) *big.Int {
return UncleReward
}
func (bm *BlockManager) AccumelateRewards(processor *Block, block *Block) error {
// Get the coinbase rlp data
addr := processor.GetAddr(block.Coinbase)
// Reward amount of ether to the coinbase address
addr.AddFee(CalculateBlockReward(block, len(block.Uncles)))
processor.UpdateAddr(block.Coinbase, addr)
for _, uncle := range block.Uncles {
uncleAddr := processor.GetAddr(uncle.Coinbase)
uncleAddr.AddFee(CalculateUncleReward(uncle))
processor.UpdateAddr(uncle.Coinbase, uncleAddr)
}
return nil
}
func (bm *BlockManager) Stop() {
bm.bc.Stop()
}
func (bm *BlockManager) ProcessContract(tx *Transaction, block *Block) {
// Recovering function in case the VM had any errors
defer func() {
if r := recover(); r != nil {
fmt.Println("Recovered from VM execution with err =", r)
}
}()
// Process contract
bm.ProcContract(tx, block, func(opType OpType) bool {
// TODO turn on once big ints are in place
//if !block.PayFee(tx.Hash(), StepFee.Uint64()) {
// return false
//}
return true // Continue
})
}
// Contract evaluation is done here.
func (bm *BlockManager) ProcContract(tx *Transaction, block *Block, cb TxCallback) {
// Instruction pointer
pc := 0
blockInfo := bm.bc.BlockInfo(block)
contract := block.GetContract(tx.Hash())
if contract == nil {
fmt.Println("Contract not found")
return
}
Pow256 := ethutil.BigPow(2, 256)
if ethutil.Config.Debug {
fmt.Printf("# op arg\n")
}
out:
for {
// The base big int for all calculations. Use this for any results.
base := new(big.Int)
// XXX Should Instr return big int slice instead of string slice?
// Get the next instruction from the contract
//op, _, _ := Instr(contract.state.Get(string(Encode(uint32(pc)))))
nb := ethutil.NumberToBytes(uint64(pc), 32)
o, _, _ := ethutil.Instr(contract.State().Get(string(nb)))
op := OpCode(o)
if !cb(0) {
break
}
if ethutil.Config.Debug {
fmt.Printf("%-3d %-4s\n", pc, op.String())
}
switch op {
case oSTOP:
break out
case oADD:
x, y := bm.stack.Popn()
// (x + y) % 2 ** 256
base.Add(x, y)
base.Mod(base, Pow256)
// Pop result back on the stack
bm.stack.Push(base)
case oSUB:
x, y := bm.stack.Popn()
// (x - y) % 2 ** 256
base.Sub(x, y)
base.Mod(base, Pow256)
// Pop result back on the stack
bm.stack.Push(base)
case oMUL:
x, y := bm.stack.Popn()
// (x * y) % 2 ** 256
base.Mul(x, y)
base.Mod(base, Pow256)
// Pop result back on the stack
bm.stack.Push(base)
case oDIV:
x, y := bm.stack.Popn()
// floor(x / y)
base.Div(x, y)
// Pop result back on the stack
bm.stack.Push(base)
case oSDIV:
x, y := bm.stack.Popn()
// n > 2**255
if x.Cmp(Pow256) > 0 {
x.Sub(Pow256, x)
}
if y.Cmp(Pow256) > 0 {
y.Sub(Pow256, y)
}
z := new(big.Int)
z.Div(x, y)
if z.Cmp(Pow256) > 0 {
z.Sub(Pow256, z)
}
// Push result on to the stack
bm.stack.Push(z)
case oMOD:
x, y := bm.stack.Popn()
base.Mod(x, y)
bm.stack.Push(base)
case oSMOD:
x, y := bm.stack.Popn()
// n > 2**255
if x.Cmp(Pow256) > 0 {
x.Sub(Pow256, x)
}
if y.Cmp(Pow256) > 0 {
y.Sub(Pow256, y)
}
z := new(big.Int)
z.Mod(x, y)
if z.Cmp(Pow256) > 0 {
z.Sub(Pow256, z)
}
// Push result on to the stack
bm.stack.Push(z)
case oEXP:
x, y := bm.stack.Popn()
base.Exp(x, y, Pow256)
bm.stack.Push(base)
case oNEG:
base.Sub(Pow256, bm.stack.Pop())
bm.stack.Push(base)
case oLT:
x, y := bm.stack.Popn()
// x < y
if x.Cmp(y) < 0 {
bm.stack.Push(ethutil.BigTrue)
} else {
bm.stack.Push(ethutil.BigFalse)
}
case oLE:
x, y := bm.stack.Popn()
// x <= y
if x.Cmp(y) < 1 {
bm.stack.Push(ethutil.BigTrue)
} else {
bm.stack.Push(ethutil.BigFalse)
}
case oGT:
x, y := bm.stack.Popn()
// x > y
if x.Cmp(y) > 0 {
bm.stack.Push(ethutil.BigTrue)
} else {
bm.stack.Push(ethutil.BigFalse)
}
case oGE:
x, y := bm.stack.Popn()
// x >= y
if x.Cmp(y) > -1 {
bm.stack.Push(ethutil.BigTrue)
} else {
bm.stack.Push(ethutil.BigFalse)
}
case oNOT:
x, y := bm.stack.Popn()
// x != y
if x.Cmp(y) != 0 {
bm.stack.Push(ethutil.BigTrue)
} else {
bm.stack.Push(ethutil.BigFalse)
}
// Please note that the following code contains some
// ugly string casting. This will have to change to big
// ints. TODO :)
case oMYADDRESS:
bm.stack.Push(ethutil.BigD(tx.Hash()))
case oTXSENDER:
bm.stack.Push(ethutil.BigD(tx.Sender()))
case oTXVALUE:
bm.stack.Push(tx.Value)
case oTXDATAN:
bm.stack.Push(big.NewInt(int64(len(tx.Data))))
case oTXDATA:
v := bm.stack.Pop()
// v >= len(data)
if v.Cmp(big.NewInt(int64(len(tx.Data)))) >= 0 {
bm.stack.Push(ethutil.Big("0"))
} else {
bm.stack.Push(ethutil.Big(tx.Data[v.Uint64()]))
}
case oBLK_PREVHASH:
bm.stack.Push(ethutil.BigD(block.PrevHash))
case oBLK_COINBASE:
bm.stack.Push(ethutil.BigD(block.Coinbase))
case oBLK_TIMESTAMP:
bm.stack.Push(big.NewInt(block.Time))
case oBLK_NUMBER:
bm.stack.Push(big.NewInt(int64(blockInfo.Number)))
case oBLK_DIFFICULTY:
bm.stack.Push(block.Difficulty)
case oBASEFEE:
// e = 10^21
e := big.NewInt(0).Exp(big.NewInt(10), big.NewInt(21), big.NewInt(0))
d := new(big.Rat)
d.SetInt(block.Difficulty)
c := new(big.Rat)
c.SetFloat64(0.5)
// d = diff / 0.5
d.Quo(d, c)
// base = floor(d)
base.Div(d.Num(), d.Denom())
x := new(big.Int)
x.Div(e, base)
// x = floor(10^21 / floor(diff^0.5))
bm.stack.Push(x)
case oSHA256, oSHA3, oRIPEMD160:
// This is probably save
// ceil(pop / 32)
length := int(math.Ceil(float64(bm.stack.Pop().Uint64()) / 32.0))
// New buffer which will contain the concatenated popped items
data := new(bytes.Buffer)
for i := 0; i < length; i++ {
// Encode the number to bytes and have it 32bytes long
num := ethutil.NumberToBytes(bm.stack.Pop().Bytes(), 256)
data.WriteString(string(num))
}
if op == oSHA256 {
bm.stack.Push(base.SetBytes(ethutil.Sha256Bin(data.Bytes())))
} else if op == oSHA3 {
bm.stack.Push(base.SetBytes(ethutil.Sha3Bin(data.Bytes())))
} else {
bm.stack.Push(base.SetBytes(ethutil.Ripemd160(data.Bytes())))
}
case oECMUL:
y := bm.stack.Pop()
x := bm.stack.Pop()
//n := bm.stack.Pop()
//if ethutil.Big(x).Cmp(ethutil.Big(y)) {
data := new(bytes.Buffer)
data.WriteString(x.String())
data.WriteString(y.String())
if secp256k1.VerifyPubkeyValidity(data.Bytes()) == 1 {
// TODO
} else {
// Invalid, push infinity
bm.stack.Push(ethutil.Big("0"))
bm.stack.Push(ethutil.Big("0"))
}
//} else {
// // Invalid, push infinity
// bm.stack.Push("0")
// bm.stack.Push("0")
//}
case oECADD:
case oECSIGN:
case oECRECOVER:
case oECVALID:
case oPUSH:
pc++
bm.stack.Push(bm.mem[strconv.Itoa(pc)])
case oPOP:
// Pop current value of the stack
bm.stack.Pop()
case oDUP:
// Dup top stack
x := bm.stack.Pop()
bm.stack.Push(x)
bm.stack.Push(x)
case oSWAP:
// Swap two top most values
x, y := bm.stack.Popn()
bm.stack.Push(y)
bm.stack.Push(x)
case oMLOAD:
x := bm.stack.Pop()
bm.stack.Push(bm.mem[x.String()])
case oMSTORE:
x, y := bm.stack.Popn()
bm.mem[x.String()] = y
case oSLOAD:
// Load the value in storage and push it on the stack
x := bm.stack.Pop()
// decode the object as a big integer
decoder := ethutil.NewValueFromBytes([]byte(contract.State().Get(x.String())))
if !decoder.IsNil() {
bm.stack.Push(decoder.BigInt())
} else {
bm.stack.Push(ethutil.BigFalse)
}
case oSSTORE:
// Store Y at index X
x, y := bm.stack.Popn()
contract.State().Update(x.String(), string(ethutil.Encode(y)))
case oJMP:
x := int(bm.stack.Pop().Uint64())
// Set pc to x - 1 (minus one so the incrementing at the end won't effect it)
pc = x
pc--
case oJMPI:
x := bm.stack.Pop()
// Set pc to x if it's non zero
if x.Cmp(ethutil.BigFalse) != 0 {
pc = int(x.Uint64())
pc--
}
case oIND:
bm.stack.Push(big.NewInt(int64(pc)))
case oEXTRO:
memAddr := bm.stack.Pop()
contractAddr := bm.stack.Pop().Bytes()
// Push the contract's memory on to the stack
bm.stack.Push(getContractMemory(block, contractAddr, memAddr))
case oBALANCE:
// Pushes the balance of the popped value on to the stack
d := block.State().Get(bm.stack.Pop().String())
ether := NewAddressFromData([]byte(d))
bm.stack.Push(ether.Amount)
case oMKTX:
value, addr := bm.stack.Popn()
from, length := bm.stack.Popn()
j := 0
dataItems := make([]string, int(length.Uint64()))
for i := from.Uint64(); i < length.Uint64(); i++ {
dataItems[j] = string(bm.mem[strconv.Itoa(int(i))].Bytes())
j++
}
// TODO sign it?
tx := NewTransaction(addr.Bytes(), value, dataItems)
// Add the transaction to the tx pool
bm.TransactionPool.QueueTransaction(tx)
case oSUICIDE:
//addr := bm.stack.Pop()
}
pc++
}
}
// Returns an address from the specified contract's address
func getContractMemory(block *Block, contractAddr []byte, memAddr *big.Int) *big.Int {
contract := block.GetContract(contractAddr)
if contract == nil {
log.Panicf("invalid contract addr %x", contractAddr)
}
val := contract.State().Get(memAddr.String())
// decode the object as a big integer
decoder := ethutil.NewValueFromBytes([]byte(val))
if decoder.IsNil() {
return ethutil.BigFalse
}
return decoder.BigInt()
}
